Now I get to compare it to the Sony 10-18mm f/4 I tested the other day (just quick sample shots on NEX 7 that belonged to a rep). I accidentally caused an uproar in the Sony NEX forums over that lens. I liked it fine, but evidently they thought the samples were pretty terrible (it is bad in the corners at 10mm f/4 and has a lot of CA everywhere), and my flickr stream got over 6000 views today because of it (this is something like 2% of my views over the last several years).

the samples that I had seen with the 12-24 were very good imo. distortion at 12mm though is expected. CA though looks acceptable. colors looked accurate. maybe I'll try the lens eventually. my feeling is that the lens will perform exactly like the 16mm's resolving power minus the weird distortion.